Work

Experience

1. Solo Engineer, SoftPOS Platform (Backend + POS App) · ITE

   Banking partner: VietinBank

   2026 - Present

   • Built a SoftPOS payment app for Android-based POS devices that accepts contactless (NFC) card payments for banking partner VietinBank, integrating the Napas MPOC SDK and Napas MAP gateway.
   • Delivered the system end to end as a solo engineer using an AI-assisted development workflow (Claude Code), accelerating delivery while owning the architecture and all design decisions.
   • Architected the backend on Clean / Hexagonal Architecture (Java 21, Spring Boot 3.5) with clear domain, application and infrastructure separation for testability and long-term maintainability.
   • Implemented OAuth2 + JWT (RSA-256) with long-lived refresh tokens so POS devices stay active without re-login, plus session tracking for token revocation.
   • Integrated the Napas MAP gateway for NFC card and QR payment flows; handled instant payment notifications (IPN), transaction void and reconciliation.
   • Built the POS device app (Android, Kotlin, Jetpack Compose) with NFC HCE emulating an NFC Type 4 Tag, transaction history (search / filter / pagination) and thermal HTML receipt printing.

   Java 21 · Spring Boot 3.5 · PostgreSQL · OAuth2/JWT · MQTT · Docker · Kotlin · Jetpack Compose · Napas MPOC SDK · NFC HCE

2. .NET Leader / Technical Lead · ITE

   2022 - Present

   • Revived and shipped a stalled product (frozen ~2 years) by diagnosing the root issues and restructuring its architecture.
   • Led the migration from a monolith to microservices, improving scalability and performance.
   • Integrated multiple payment methods and hardened authentication & authorization with IdentityServer.
   • Built and maintained a fully automated CI/CD pipeline (GitLab CI + Jenkins + Docker).
   • Planned work, allocated tasks and coached an 8-member engineering team.
   • Integrated OpenAI into the product to automate reporting, improve content quality and cut manual effort.
   • Defined and rolled out an AI-assisted development workflow across the SDLC (planning, coding, review), and trained the team on agentic coding tools (Claude Code, Claude Co-Work), driving adoption and faster delivery.

   .NET Core · IdentityServer · PostgreSQL · Ocelot · Redis · Selenium · ELK · Jenkins · Docker · Portainer · MinIO

3. Senior Backend Developer · FPT Software

   2021 - 2022

   • Optimized API performance, cutting response times and resource usage.
   • Worked directly with clients in Singapore and France to analyze and solve complex technical issues.
   • Ran code reviews and mentored the team on backend best practices.

   .NET Core · MS SQL

4. Sub-Team Leader / Backend Developer · ITE

   2019 - 2021

   • Built and optimized a secure payment gateway & routing platform for major partners (VNPost, ViettelPay, Bamboo).
   • Led integration, SIT and release activities; improved internal Git workflows.
   • Set up and maintained the company GitLab server and internal infrastructure.

   Java · Spring Boot · Tomcat · Oracle · MySQL · MongoDB · Linux · GCP · Jenkins · Docker

5. Backend Developer · FiinGroup

   2019

   • Built a real-time processing service for stock-exchange data (HNX & HOSE).
   • Sustained high throughput and low latency under peak load.

   .NET Core · MS SQL · Redis

6. Backend Developer · NashTech / Harvey Nash

   2018 - 2019

   • Delivered performance improvements within a 16-member project team.
   • Added robust unit tests and improved backend reliability.

   .NET Framework · MS SQL

7. Backend Developer · VNPAY

   2017 - 2018

   • Built VNPAY's recruitment website and internal tools.
   • Built a mobile web app for TPBank's airline-ticket purchasing flow.
   • Integrated the VNPay payment gateway.

   .NET Framework · Oracle · JavaScript · Framework7

Selected projects

1. Agentic Automation & AI Tooling

   Self-directed

   • Operate a fleet of Claude Code agents orchestrated over Telegram (parallel task delegation, scheduled jobs, owner-only access control), backed by self-built infrastructure: a self-hosted mempalace MCP server for centralized long-term memory shared across agent sessions and machines, plus a self-built voice-mcp service giving the agents speech-to-text and text-to-speech.
   • Built agentic automation with Claude (Anthropic) via the Model Context Protocol (MCP), wired to tools like Notion and Jira and driven hands-free through a Telegram bot.
   • Designed event-driven automation pipelines (n8n, webhooks) connecting LLMs to messaging and productivity systems.
   • Built a chat-with-AI product POC (ChatGPT / Claude-chat style) backed by Retrieval-Augmented Generation (RAG) over a private knowledge base, with OpenTelemetry usage observability tracking token cost and latency.

   Claude (Anthropic) · OpenAI API · MCP · mempalace · voice-mcp · n8n · OpenTelemetry · Python · Bash

2. Claude Code Observability (ccobs)

   Open-source

   • Built an end-to-end observability stack for AI (Claude Code) usage: OpenTelemetry Collector to Prometheus, Loki and Grafana, packaged as an all-in-one Docker image with per-device token management; automated build and release via GitHub Actions to GHCR.

   OpenTelemetry · Prometheus · Loki · Grafana · Docker · GitHub Actions

   github.com/trongnguyenbinh/Claude-Code-Observability

3. Claude Telegram Docker

   Open-source

   • Packaged a self-hosted Claude Code Telegram bot as a portable “one image = one bot” Docker container: bake the Claude CLI, the Telegram channel plugin and MCP tooling into a single multi-arch image, so a new agent is spun up with only a bot token and an owner ID.
   • Designed the deployment for headless, long-running operation: OAuth-token auth that survives volume wipes, owner-only allowlist access control, host-side admin via docker exec and a live-attachable tmux session; automated multi-arch build and release via GitHub Actions to GHCR.

   Docker · Claude Code · Telegram · MCP · tmux · GitHub Actions · GHCR

   github.com/trongnguyenbinh/claude-telegram-docker

4. voice-mcp: Speech I/O for AI Agents

   Open-source

   • Built a self-hosted voice endpoint giving AI agents both speech-to-text and text-to-speech through one service, exposed over both an MCP (streamable-HTTP) interface and a plain REST API with bearer-token auth.
   • Ran STT on faster-whisper (CPU int8) and TTS via gTTS with an optional Google Cloud TTS fallback; server-side ffmpeg transcodes to Ogg/Opus so clips render as native Telegram voice bubbles, and speak returns a cached-file URL instead of a base64 blob. Packaged as a Docker image, keeping all audio on self-hosted infrastructure.

   Python · MCP · faster-whisper · gTTS · ffmpeg · Docker · REST

   github.com/trongnguyenbinh/voice-mcp

Toolbox

Languages

C#/.NET, Java, Kotlin, SQL, Bash

Frameworks

ASP.NET Core, Spring Boot, Jetpack Compose

Architecture

Microservices, Clean/Hexagonal, DDD, REST, OAuth2/JWT (IdentityServer)

Databases

PostgreSQL, MS SQL, MySQL, Oracle, MongoDB, Redis, Elasticsearch

DevOps / CI-CD

Docker, Portainer, Jenkins, GitLab CI, GitLab Runner, GitHub Actions, Git

Monitoring

Prometheus, Grafana, ELK (Logstash, Kibana), OpenTelemetry

Messaging / Gateways

MQTT, Nginx, Ocelot

AI / LLM

Claude (Anthropic), Claude Code, Co-Work, OpenAI API, LLM Agents, MCP, mempalace, voice-mcp, Prompt Engineering, RAG

Cloud / OS

GCP, Linux, Windows

Certifications

• Model Context Protocol: Advanced TopicsJun 2026

  Anthropic Education · verify.skilljar.com/c/37hnk57es25n

• Claude Code in ActionJun 2026

  Anthropic Education · verify.skilljar.com/c/6h3erba8a6mg

• Claude with Amazon BedrockJul 2026

  Anthropic Education · verify.skilljar.com/c/rydnqmqzqvgp

Education